Chromosome anomalies in 136 couples with a history of recurrent abortions.

Cytogenetic studies were performed on 136 couples with a history of two or more abortions referred to us after gynaecological causes of the abortions had been excluded. Fifteen (11%) of the couples were found to have a chromosome anomaly, and when the couples were subdivided according to number of abortions, surprisingly 6 (10%) of the 59 couples with a history of only two abortions had a chromosome anomaly. An increased frequency of mosaicism for X-chromosome aneuploidy (2.2%) in the women from the 136 couples was also found. A review of the literature shows that translocations of some chromosomes (e.g. nos. 1, 7 or 22) preferentially lead to fetal wastage, while those involving, for example, chromosome nos. 5, 9, 14 or 21 are more likely to result in the birth of a handicapped child. Couples with a history of two abortions should be investigated cytogenetically. Other causes of miscarriages must, however, be excluded first.